Pham Tony, Forrest Katherine A, Gao Wen-Yang, Ma Shengqian, Space Brian
Department of Chemistry, University of South Florida, 4202 E. Fowler Ave., CHE205, Tampa, FL, 33620-5250, USA.
Chemphyschem. 2015 Oct 26;16(15):3170-9. doi: 10.1002/cphc.201500504. Epub 2015 Aug 25.
Theoretical investigations of CO2 sorption are performed in four members of the highly tunable rht-metal-organic framework (MOF) platform. rht-MOFs contain two Cu(2+) ions that comprise the metal paddlewheels and both are in chemically distinct environments. Indeed, one type of Cu(2+) ion faces toward the center of the linker whereas the other type faces away from the center of the linker. Electronic structure calculations on the series of rht-MOFs demonstrate that one of the Cu(2+) ions has a consistently higher charge magnitude relative to the other. As a consequence, the Cu(2+) ion with the higher partial positive charge acts as the favored sorbate binding site at initial loading as revealed by grand canonical Monte Carlo (GCMC) simulations that include many-body polarization. It was found that the charge distribution about the copper paddlewheels is dependent on the type of functional groups present on the linker. This study demonstrates how the binding site about the metal paddlewheels in the rht-MOF platform can be controlled by changing the functionality on the organic ligand.
在高度可调谐的rht-金属有机框架（MOF）平台的四个成员中进行了二氧化碳吸附的理论研究。rht-MOF包含两个构成金属桨轮的Cu(2+)离子，且二者处于化学性质不同的环境中。实际上，一种类型的Cu(2+)离子朝向连接体的中心，而另一种类型则背离连接体的中心。对该系列rht-MOF进行的电子结构计算表明，其中一个Cu(2+)离子相对于另一个具有始终更高的电荷值。因此，如包含多体极化的巨正则蒙特卡罗（GCMC）模拟所示，具有较高部分正电荷的Cu(2+)离子在初始负载时充当有利的吸附质结合位点。研究发现，围绕铜桨轮的电荷分布取决于连接体上存在的官能团类型。这项研究展示了如何通过改变有机配体上的官能团来控制rht-MOF平台中金属桨轮周围的结合位点。
